APPENDIX D LIST OF CAUTIONS
User’s Manual U17446EJ3V1UD
401
(19/19)
Chapter
Cl
assi
fi
cati
on
Function Details
of
Function
Cautions Page
Absolute
maximum ratings
Product quality may suffer if the absolute maximum rating is exceeded even
momentarily for any parameter. That is, the absolute maximum ratings are
rated values at which the product is on the verge of suffering physical damage,
and therefore the product must be used under conditions that ensure that the
absolute maximum ratings are not exceeded.
p.338
X1 oscillator
When using the X1 oscillator, wire as follows in the area enclosed by the
broken lines in the above figures to avoid an adverse effect from wiring
capacitance.
• Keep the wiring length as short as possible.
• Do not cross the wiring with the other signal lines.
• Do not route the wiring near a signal line through which a high fluctuating
current flows.
• Always make the ground point of the oscillator capacitor the same potential
as V
SS
.
• Do not ground the capacitor to a ground pattern through which a high current
flows.
• Do not fetch signals from the oscillator.
p.339
Chapter 2
1
Hard
Electrical
specifica-
tions
(Standard
product,
(A) grade
product)
A/D converter
The conversion accuracy may be degraded if the analog input pin is used as
an alternate I/O port or if a port is changed during A/D conversion.
p.346
−
These specifications show target values, which may change after device
evaluation. The operating voltage range may also change.
p.350
Absolute
maximum ratings
Product quality may suffer if the absolute maximum rating is exceeded even
momentarily for any parameter. That is, the absolute maximum ratings are
rated values at which the product is on the verge of suffering physical damage,
and therefore the product must be used under conditions that ensure that the
absolute maximum ratings are not exceeded.
p.350
X1 oscillator
When using the X1 oscillator, wire as follows in the area enclosed by the
broken lines in the above figures to avoid an adverse effect from wiring
capacitance.
• Keep the wiring length as short as possible.
• Do not cross the wiring with the other signal lines.
• Do not route the wiring near a signal line through which a high fluctuating
current flows.
• Always make the ground point of the oscillator capacitor the same potential
as V
SS
.
• Do not ground the capacitor to a ground pattern through which a high current
flows.
• Do not fetch signals from the oscillator.
p.352
Chapter 2
2
Hard
Electrical
specifica-
tions
(Target
values)
((A2) grade
product)
A/D converter
The conversion accuracy may be degraded if the analog input pin is used as
an alternate I/O port or if a port is changed during A/D conversion.
p.359
Lead-free
products
Products with -A at the end of the part number are lead-free products.
p.365
For soldering methods and conditions other than those recommended below,
contact an NEC Electronics sales representative.
p.365
pp.
Chapter 2
4
Hard
Recom-
mended
soldering
conditions
−
Do not use different soldering methods together (except for partial heating).
365, 366